Machines known as sliding form machines are already known in the art in which a predetermined amount of cement concrete is deposited on the ground by feeder means, then subjected to a forming under vibration using upper and side form plates mounted solid with the frame.
However, in this type of machine the concrete layer is made between the supports of the machine, which requires the use of a tractor unit of the straddling type, whose side bulk is disadvantageously great. This type of machine therefore imposes a limit on the width of the slab to be made which is compatible with the tractor path itself, except for major mechanical interventions.
Moreover, this type of requires a complex altimetric guide system with a minimum of four height-adjusting jacks which act as rigid connections between the sliding form and the frame of the machine. These jacks are provided to compensate for the defects of the traveling surface of the tractor unit, by preventing these defects from impacting on the quality, or smoothness, of the layer of concrete formed. In particular, such a system is most often poorly suited to compensating for sudden movements or impacts, both vertical and horizontal, exerted on the machine.